Image forming apparatus

Abstract

An image forming apparatus can suppress the degradation of an image signal due to electrostatic discharge with a simple configuration. An original feeder unit is supported openably and closably by a hinge mechanism fixed on a bottom member of an image reading unit. An image sensor substrate of an image reading unit and an image processing substrate of an image forming unit are connected by a cable. An electrically conductive connecting portion electrically connects a bottom member of the image reading unit with a casing of the image forming unit, and is arranged along the cable. The bottom member has a notch formed therein, the connecting portion is fixed to the bottom member so as to extend over the notch, and the cable is arranged so as to pass through an opening portion thereby formed in a direction from above to below of the bottom member.

What is claimed is: 
     
       1. An image forming apparatus comprising:
 an electrically conductive member; 
 a platen disposed above the electrically conductive member; 
 an image reading unit, disposed between the electrically conductive member and the platen, and having an image reading portion configured to scan an original placed on the platen, for reading out an original image; 
 an image forming unit comprising:
 an electrically conductive casing, 
 an image processing portion connected to the image reading portion by a cable, to receive an image signal from the image reading portion by the cable and to process the image signal, and 
 an image forming portion disposed inside of the electrically conductive casing, and forming an image, based on a result of the image processing by the image processing portion; 
 
 an opening and closing member configured to open and close a surface of the platen; 
 an electrically conductive hinge member fixed to the electrically conductive member, and facilitating opening and closing of the opening and closing member; and 
 an electrically conductive connecting portion for causing electrical continuity from the electrically conductive member to the electrically conductive casing, wherein 
 the cable passes through an opening portion surrounded by the electrically conductive connecting portion and the electrically conductive member. 
 
     
     
       2. The image forming apparatus according to  claim 1 , wherein
 the opening and closing member comprises an original feeder unit for feeding the original to the platen. 
 
     
     
       3. The image forming apparatus according to  claim 1 , wherein
 the electrically conductive connecting portion is formed by a member separate from the electrically conductive member, 
 the electrically conductive member has a notch formed to pass therethrough the cable, and 
 the opening portion is formed, such that the electrically conductive connecting portion is extended over the notch of the electrically conductive member to be fixed to the electrically conductive member. 
 
     
     
       4. The image forming apparatus according to  claim 1 , further comprising
 an insulating member holding the opening portion and the cable separately from each other. 
 
     
     
       5. The image forming apparatus according to  claim 1 , further comprising
 an electrically conductive top member connected to an upper portion of the electrically conductive casing, wherein 
 the electrically conductive connecting portion is connected to the electrically conductive top member, and connected electrically through the electrically conductive top member to the electrically conductive casing. 
 
     
     
       6. The image forming apparatus according to  claim 5 , wherein
 the electrically conductive connecting portion has a second opening portion formed to pass therethrough the cable in a direction from above the electrically conductive top member to below the electrically conductive top member. 
 
     
     
       7. The image forming apparatus according to  claim 6 , wherein
 the electrically conductive connecting portion is formed from a member separate from the electrically conductive top member, 
 the electrically conductive top member has a notch formed to pass therethrough the cable, and 
 the second opening portion is formed, such that the electrically conductive connecting portion is extended over the notch of the electrically conductive top member to be fixed to the electrically conductive top member. 
 
     
     
       8. The image forming apparatus according to  claim 6 , further comprising
 an insulating member holding the second opening portion and the cable separately from each other. 
 
     
     
       9. The image forming apparatus according to  claim 1 , further comprising
 an electrically conductive box, in which the image processing portion is arranged, fixed to a side portion of the electrically conductive casing, wherein 
 the electrically conductive connecting portion is connected to the electrically conductive box and has electrical continuity through the electrically conductive box to the electrically conductive casing. 
 
     
     
       10. The image forming apparatus according to  claim 9 , wherein
 the electrically conductive connecting portion has a second opening portion formed to pass therethrough the cable in a direction from above the electrically conductive box to below the electrically conductive box. 
 
     
     
       11. The image forming apparatus according to  claim 10 , wherein
 the electrically conductive connecting portion is formed from a member separate from the electrically conductive box, 
 the electrically conductive box has an opening at a side surface thereof formed to be covered by the electrically conductive connecting portion, 
 the electrically conductive box has, at an upper surface thereof, a notch formed to be communicated with the opening and to pass therethrough the cable, 
 the electrically conductive connecting portion is fixed to the side surface of the electrically conductive box, and 
 the second opening portion is formed in the upper surface of the electrically conductive box. 
 
     
     
       12. The image forming apparatus according to  claim 10 , further comprising
 an insulating member holding the second opening portion and the cable separately from each other.